Pauli refers to an introduction by Bernays to a discussion on probability in: Dialectica : 7, no.4, and makes some critical remarks on Bernays's statement at the end of his introduction (p. 321).

The letter contains a short remark on self-energy and a longer one meson-theory, with reference to papers by Schwinger and Oppenheimer.

The letter talks about some results of the application of "substraction-quantumelectrodynamics" to a higher approximation of the Compton-effect.

Pauli recommends his assistant Jost to Bethe. He gives a critical comments on a paper by Dyson about regularization.

Pauli gives additional remarks to a paper by S T Epstein on self-energy. He comments on the physical significance of auxiliary particles. The letter mentions his work on D-factors, appearing in connection with the Lambshift and the magnetic moment of the electron.

Pauli makes a remark on a note by Bethe on self-energy in: Physical review, 55, 681, 1939.

Pauli thanks Bhabha for his letter of the 26th March. He gives developments about meson and proton dispersion and comments on Bethe's latest work on meson theory and nuclear power and also his interpretation based on Fierz's study of Blau and Wambacher's results. Pauli sees a solution in new particles that have been observed in cosmic radiation. Heitlers theory seems to be unsatisfying. Pauli is working on a theory on high speed particles. He adds some remarks on the war and some physicists.

Pauli writes that there could be some possibilities of a position in the USA for Bhabha. He is publishing his Solvay report of 1939 in the Rev. Mod. Phys. Observations on Christy and Kusaka's calculations on the development of the shower and the pseudo scalar meson theory.

Pauli made some additions to Bhabha's paper for the Bohr Festschrift. He says it is impossible to quantize the Bhabha equation according to Fermi-Dirac statistics without using an indefinite metric in Hilbert-space. Pauli says he will know his future plans better in six months, including the possibility of a visit to the Tata-Institute (India).

Pauli thanks him for his congratulations concerning the Nobel ceremony and he reports on the physics meeting in New York at the end of January. Pauli is going on a trip with his wife in four weeks to Europe.